BTCMarkets: Fix testexch.Setup not finding config

BTCMarkets is the only example where config name doesn't match the
package name.
Renaming it shouldn't have any impact.
Users having different names locally for it in config shouldn't either

config_example.json

@@ -262,7 +262,7 @@
  },
  "exchanges": [
   {
-   "name": "BTC Markets",
+   "name": "BTCMarkets",
    "enabled": true,
    "verbose": false,
    "httpTimeout": 15000000000,

exchanges/btcmarkets/btcmarkets_test.go

@@ -3,7 +3,6 @@ package btcmarkets
 import (
 	"context"
 	"errors"
-	"fmt"
 	"log"
 	"os"
 	"testing"
@@ -12,7 +11,6 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/thrasher-corp/gocryptotrader/common"
-	"github.com/thrasher-corp/gocryptotrader/config"
 	"github.com/thrasher-corp/gocryptotrader/currency"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/asset"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/kline"
@@ -37,30 +35,19 @@ const (
 )
 
 func TestMain(m *testing.M) {
-	b.SetDefaults()
-	cfg := config.GetConfig()
-	err := cfg.LoadConfig("../../testdata/configtest.json", true)
-	if err != nil {
-		log.Fatal(err)
-	}
-	bConfig, err := cfg.GetExchangeConfig("BTC Markets")
-	if err != nil {
-		log.Fatal(err)
-	}
-	bConfig.API.Credentials.Key = apiKey
-	bConfig.API.Credentials.Secret = apiSecret
-	bConfig.API.AuthenticatedSupport = true
-	b.Websocket = sharedtestvalues.NewTestWebsocket()
-	err = b.Setup(bConfig)
-	if err != nil {
+	b = new(BTCMarkets)
+	if err := testexch.Setup(b); err != nil {
 		log.Fatal(err)
 	}
-	err = b.ValidateAPICredentials(context.Background(), asset.Spot)
-	if err != nil {
-		fmt.Println("API credentials are invalid:", err)
-		b.API.AuthenticatedSupport = false
-		b.API.AuthenticatedWebsocketSupport = false
+
+	if apiKey != "" && apiSecret != "" {
+		b.API.AuthenticatedSupport = true
+		b.API.AuthenticatedWebsocketSupport = true
+		b.API.CredentialsValidator.RequiresBase64DecodeSecret = false
+		b.SetCredentials(apiKey, apiSecret, "", "", "", "")
+		b.Websocket.SetCanUseAuthenticatedEndpoints(true)
 	}
+
 	os.Exit(m.Run())
 }
 

testdata/configtest.json

@@ -242,7 +242,7 @@
  },
  "exchanges": [
   {
-   "name": "BTC Markets",
+   "name": "BTCMarkets",
    "enabled": true,
    "verbose": false,
    "httpTimeout": 15000000000,